What does the classical Chinese text "The Name Luosun Mountain" mean?

Original text: Sun Shan, a native of Wu, was a funny and talented person. When I went to Juta County, the villagers asked me to take my son with me. The countryman is frustrated, he is at the bottom of the mountain list, and returns first. A villager asked about his son's gains and losses, and Shan said: "It is Sun Shan who knows his name, and the virtuous man is outside Sun Shan."

Translation:

In the Song Dynasty, there was a man A talented man named Sun Shan was not only humorous but also good at telling jokes, so people nearby gave him the nickname "Funny Talent". Once, he went to the capital with the son of a fellow villager to take the exam.

When the list was released, although Sun Shan's name was listed at the bottom of the list, he was still on the list, but the son of the fellow countryman who went with him was not. Didn't pass the exam. Soon, Sun Shanxian returned home, and his fellow villagers came to ask if his son had passed the exam. Sun Shan was embarrassed to speak directly, but also couldn't hide it, so he read out two lines of poetry: "Sun Shan is the one who knows the name, and the virtuous man is outside Sun Shan."

The idiom allusion of "The name falls from Sun Shan"

In the Song Dynasty of our country, there was a talented man named Sun Shan. He was not only humorous, but also good at telling jokes, so people nearby gave him the name "Sun Shan". The nickname "Funny Talent".

Once, he and the son of a fellow villager went to the capital to take the examination.

When the list was released, although Sun Shan's name was listed at the bottom of the list, it was still on the list, but the son of the fellow countryman who went with him was not. Passed the exam.

Soon after Sun Shan returned home, his fellow villagers came to ask if his son had passed the exam. Sun Shan was embarrassed to speak directly and couldn't hide it, so he casually read out two lines of poetry:

"Sun Shan is the one who knows the name, and the virtuous man is outside Sun Shan." "

The whole meaning of his poem is:

"The last one on the list is me, Sun Shan, but my son's name is still behind my Sun Shan. ”

From then on, based on this story, people called it “famous failure” when applying to a school or taking various exams but not being admitted.